Electron discharge device



July 9, 1940. R. c. HERGENRQTHER 2,206,954

ELECTRON DISCHARGE DEVICE Filed Aug. 13. 1938 INVENTOR yLF O. HERGENROTHER B ATTORNEY Patented July 9, 1940 UNITE-D STATES PATENT- OFFICE.

ELECTRON nrsonnaon ev ce Rudolf c. Hergenrother, Beechhurst, N. "11., assignor to Hazeltine Corporation, a corporation of Delaware Application August 13, 1938, Serial No. 224,661

8 Claims. (Cl. 250-215) This invention relates generally to electron stream emitted by the cathode into two flat. beams discharge devices having a fluorescent screen and for forming luminous ribbons on the fluorescent particularly to'such devices in which the intenscreen, the electrode means comprising a single sity of illumination of the screen is a function of pair of deflecting electrodes and the relative posithe control *potentials applied to the device. tion of said beams being a function of the poten- 5 While the invention is of general utility, it is tials applied to the pair of deflecting electrodes. particularly useful as a tuning indicator in modu- Preferably the electron directing means comlated-carrier signal-receiving apparatus. prises protruding portions of the anode together Electron discharge devices having luminous with a deflector electrode disposed therebetween.

l0 fluorescent screens have commonly beenused as Also, in accordance with the preferred embodituning indicators in wave-signal receivers. Such ment of the invention, there is provided a condevioes have generally comprised auxiliary electrol electrode between the cathode and the anode, trodes including an auxiliary cathode, mounted and the cathode, the control electrode, and. the within an envelope common to a vacuum-tube anode may be utilized in the conventional man- 1 amplifier, The auxiliary cathode of such devices her as a vacuum-tube repeater. The preferred is operated at its emission saturation point; in arrangement is such that the protrusions on the order to limit the flow of electrons to the fluoanode together with the deflector electrode efrescent screen. Such prior art devices have a fectively form ameans for'directing the electron disadvantage in that they may have a relatively beams and the preferred method of operation is I short life due to the fact that the cathode is operthat of maintaining constant the potential on 20 ated at the saturation point and have a further the deflector electrode and causing the potential disadvantage in that the number of electrons of the anode to vary as a function of a control emitted to the screen or anode is not a function voltage applied to the control electrode.

of the control potential, thereby causing the For a better understanding of the invention,

change in intensity of illumination of the screen together with other and further objects thereof, 25 to be limited to a relatively small value over the reference is, had to the following description range of operating potentials applied to the detaken in connection with the accompanying vice. Furthermore, prior art devices have com-' drawing, and its scope will be pointed out in the monly relied on a shadow angieto indicate appended claims. i

tuning, renderingthe determination of a critical In the drawing, Fig. 1 is a side elevation of an so indication somewhat difiicult. eiectron discharge device in accordance with the- It is an object of the present invention, thereinvention, the envelope being broken away; Fig. 2 1 fore, ,to provide an improved electron discharge is a perspective view of the assembly of the elec-,

device of the type described, in which'the abovetrodes of the tube; while Fig. 3' is a circuit diamentioned disadvantages are eliminated. gram illustrating the preferred method of oper- 35' It is also an object of the invention to provide 1 ation of the tube. v I an improved electrondischarge device of the Referring now'more particularly to Figs. 1 and type described which is particularly suitable for 2 of'the drawing-there is showman envelope in use as a visual tuning indicator in a wave-signal having a pressed re-entrant stem ll inwhich are 40 receiver and in which resonance is indicated by supported a plurality of lead-in wires supporting 40 a glow on a luminous screen, the brilliancy of the the electrodes of the tube. The electrodes comglow 'being a function of the degree of accuracy prise a cylindrical indirectly heated cathode i2, of tuning. heated by afllament through lead-in wires 13 It is a further object of the invention to proand M, a cylindrical grid or control electrode 15 vide an improved electron discharge device of the surrounding cathode l2 and mounted on supports 45 type described adaptable for use as a visual tuni6 and I1, and a substantially cylindrical main ing indicator in a wave-signal receiver, in which anode I8. surrounding control electrode l5 and resonance is indicated by the degree of separa i mounted on support IS. The main anode I8 is tion of two parallel ribbons on a luminous screen. provided with radially extending protrusions 20 In accordance with the invention, there is proand 2| midway between which'there is disposed 50 vided an electron discharge device including a a deflector electrode 22 mounted on supports 23 cathode, an anode, and a fluorescent screen, toand 24. In order to prevent accumulation of gether with electrode means disposed between electrons in the vicinity of the fluorescent screen the cathode and screen and forming means for of the discharge device, there is provided a coldirecting and focusing portions of'the electron lecting anode 25 mounted on, and electrically 55 connected to, deflector electrode 22, by means of supports 26 and 21. When the electrode assembly just described is assembled in envelope ID having a fluorescent screen 28 on the inner wall thereof, the passageways between deflector electrode 22 and the protrusions 20 and 2i on anode l8 are in line with cathode i2 and the screen 28, and collecting anode 25 is disposed adjacent screen 28 as shown.

In considering the characteristics of the tube just described, it will be seen that, with proper operating potentials applied to the several electrodes, protrusions 20, 2|, together with deflector electrode 22, efiectively provide means for directing portions of theelectron stream emitted by cathode l2 into two parallel beams forming parallel luminous ribbons on screen 28. The intensity of the electron stream emitted by cathode l2 and, therefore, the brilliancy of the parallel ribbons on screen 28 is a function of the control potential applied to control electrode i5. Also, the spacing of the parallel ribbons on tube 28 is a function of the difference in potential between deflector electrode 22 and anode i8.

Reference is made to Fig. 3 for an illustration of a preferred method of operation of the discharge device of the invention. Only the tube elements necessary in the description are shown. The circuit comprises a source of potential 3B, to the positive terminal of which deflector electrode 22 is directly connected and to which anode I8 is connected through a load resistor ii. In order to provide a negative-bias potential for control electrode i5, there is provided a source of potential 32 across which is connected resistance potential divider 33, control electrode l5 being connected to the adjustable tap of potential divider 83.

In considering the operation of the circuit of Fig. 3, it will be seen that the potential of deflector electrode 22 is maintained constant, while the potential of anode l8 decreases as the negative voltage applied to control electrode I5 is decreased, due to the increased current flow through load resistor 3|. Therefore, as the control voltage applied to electrode I5 is increased, the brilliance of the luminous ribbons on screen 25 increases and simultaneously a difierence in potential between protrusions 20, 2! and deflector electrode 22 results, eflectively deflecting the streams toward each other to decrease the distance between the parallel luminous ribbons.

The use of the discharge device of the invention as a tuning indicator in a wave-signal receiver is mentioned as being a particularly practical adaptation of the discharge device of the invention. The automatic amplification control-bias poten tial of the receiver may be utilized to vary the potential of grid 15 so that the distance between the parallel luminous ribbons on screen 28 and their brilliancy varies with the tuning of the receiver, the distance being a minimum when the receiver is tuned to resonance with a received signal and the ribbons then having their greatest brilliancy.

While there has been shown a structure utilizing a small aperture between element 22 and protrusions 2i! and 2i for directing the electron streams onto the screen 28, it will be understood that other'means for'producing this result may be utilized. For instance, cylindrical electron lenses, or lenses of any other type, may be utilized for focusing the electrons .into parallel ribbons on the screen.

While there has been described what is at present' considered to be the-preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is, therefore, aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. An electron discharge device including a cathode, an anode, a fluorescent screen, and electrode means disposed between said cathode and said screen and forming means for directing portions of the electron stream emitted by saidv cathode into two flat beams for forming luminous ribbons on said screen, said electrode means comprising a singlepair oi deflecting electrodes common to both of said beams and the relative position of said beams being a function of the potential applied to said pair of deflecting electrodes.

2. An electron discharge device including a cathode, an emission control electrode, an anode, a fluorescent screen, and a single deflector electrode, said anode and said deflector electrode effectively comprising means for directing portions of the electrons emitted by said cathode into two flat beams for forming two parallel luminous ribbons on said screen, said anode and said single deflector electrode comprising deflecting electrodes common to both of said beams and the relative position of said beams being a function of the potential applied between said anode and said deflector electrode and the brilliance of said beams being a function 0! the potential applied to saidcontrol electrode.

3. An electron discharge device including a cathode, a main anode, a fluorescent screen, a collector anode adjacent said screen for preventingthe accumulation'of charges thereon, and a deflector electrode, said main anode and said deflector electrode eflectively comprising two means for directing portions of the electrons emitted by said cathode into two flst'beams for forming two parallel luminous ribbons on said screen, the relative position of which is a function of the potential applied between said main anode and said deflector electrode.

4. An electron discharge device including a cylindrical cathode, an emission control electrode surrounding said cathode, a cylindrical anode substantially surrounding said control electrode and comprising a pair of elongated opposed plate- Y like members extending radially from said cathode, a deflector plate interposed between said members, and a fluorescent screen, said anode and said deflector electrode effectively comprising two means for directing portions of the electron stream emitted by said cathode into two flat beams for forming parallelluminous ribbons on said screen, the relative position of which is'a function of the potential applied between said anode and said deflector electrode.

cylindrical cathode. an l: a on control electrode surrounding said cathode, a cylindrical emcee having a longltudlnol flanged slot and. substentieily surrounding said control electrode, the flanges extending radially from sale cathode, a, deflector plate electrode dlspcsecl be tween seid fiengee and! a, fluorescent screen, said anode and said deflector electrode efiectively comprising two means for directing portions of the electron stream emitted by said cathode ioto two flee beams for forming two parallel luminous ribbons on said screen, the relative position cl which is a, motion oi the potential. epplieel between $2451 flanges seld deflector electrode.

'2. An electron dis-charge device including a cylindrical cathode, ell emission control electrode currolmrllrlg sale eellmele, a cylindrical anode hevlng e cl'slot and all *etemtlcllly surrounding said cc: electrode, 5cm extending radially fr ll seicl cathode, e ole fieetm: plate electrode between eeicl ilexlgee,

iiucrescent screen, e collector anode adjacent said screen, selcl main anode and said elelleclor electrode effectively comprising two means for cllrectirlg portions oi the electrons from cold cetlicoe into two luminous rellel rice on o; ecreerl, the relative position of well 1e e ctlon of the tentiel applied between sold ode one said deflector electre, and me electrlc connecting solo deflector ll collector anode.

8. An electron ollecree oeviee incl 1 cathode, an emission control electrode oriented be sulciecteoto e, verieble control potential. e fluorescent screen, em acetic; and e deflector elecerede, sole mode erloeelml ,cleeter electe ellectlvely conmrieilog two vre for eating portions oi the eleotrerl stream etted by we cethocle late We flel; for lormlrlg eerellei lumlnous ribeorls oil ecree elle reletlve position oil which is '2 luscetlo e oi gzoteol applied e ode eld deflector electrode cello allelic l cuilli *lo hove ice potential vex-loll lo JQQJLBMQ with mrlelione g in potezztlol eolmlml eleclrcfle, one said defiecior electrode lz-elrogg elliegcwoi be meim tamed at e eooeiserri; pol-entlol. 

